Long-term results of apical aortic conduits in children with complex left ventricular outflow tract obstruction
John W Brown1, Mark Ruzmetov, Andrew C Fiore
1Section of Cardiothoracic Surgery, James W. Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, Indiana, USA. jobrown@iupui.edu
Insights
Apical aortic conduits effectively treated complex left ventricular outflow tract obstruction in children, showing good initial results. However, late complications related to valve dysfunction led to frequent reoperations, prompting a shift to alternative procedures.
Area of Science:
- Pediatric Cardiology
- Cardiovascular Surgery
- Medical Devices
Background:
- Apical aortic conduits were utilized for complex left ventricular outflow tract obstruction in pediatric patients.
- Initial outcomes with porcine xenograft conduits were favorable, but homograft conduits yielded less satisfactory results.
- This study reviews the clinical experience with apical aortic conduits, focusing on hemodynamics, reoperation rates, and long-term outcomes.
Purpose of the Study:
- To evaluate the efficacy and long-term outcomes of apical aortic conduits in children with complex left ventricular outflow tract obstruction.
- To analyze hemodynamic improvements, reoperation rates, and survival following apical aortic conduit insertion.
- To compare early and late results of apical aortic conduits, particularly concerning valve dysfunction.
Main Methods:
- Retrospective review of 28 pediatric patients (2 weeks to 19 years) who underwent apical aortic conduit insertion between 1979 and 1993.
- All patients presented with complex multilevel left ventricular outflow tract obstruction and were symptomatic, with many having prior aortic valve interventions.
- Data collection included perioperative mortality, hemodynamic assessments via cardiac catheterization, reoperation details, and long-term survival.
Main Results:
- Hospital mortality was 11% (3 of 28).
- Significant reduction in mean left ventricular-to-aortic peak gradient was observed postoperatively (81.8 to 15.4 mm Hg, p < 0.001).
- Overall 25-year survival was 57%, with 56% of survivors requiring reoperation due to recurrent obstruction or valve dysfunction.
Conclusions:
- Apical aortic conduits provide effective short- and midterm relief of complex left ventricular outflow tract obstruction in children.
- Late complications, primarily conduit tissue valve dysfunction, are common and necessitate reoperation.
- The Ross or Ross-Konno procedures have largely superseded apical aortic conduits in pediatric practice due to these late issues.
Background:
Apical aortic conduits were used in children with complex left ventricular outflow tract obstruction at our institution before we adopted the Ross and Ross-Konno procedures. The early results with apical aortic conduits were quite good when we used a porcine xenograft conduit and were less satisfactory when we converted to an aortic homograft valve as the conduit valve. This report summarizes our clinical experience with apical aortic conduits in children with an emphasis on hemodynamic results, reoperation, and long-term follow-up.
Methods:
Records of 28 patients (age range, 2 weeks to 19 years) who underwent insertion of apical aortic conduit between September 1979 and June 1993 were reviewed. All patients had complex multilevel left ventricular outflow tract obstruction. All were symptomatic, and 22 (79%) had had one or two previous aortic valvotomies or left ventricular outflow tract operations, or both.
Results:
Hospital mortality was 11% (3 of 28). Twenty-five children survived the perioperative period and improved, and 21 have had one or more cardiac catheterization from 6 to 18 months (mean, 1.2 years) after the initial operation. Reduction or resolution of resting mean left ventricular-to-aortic peak gradient in the early postoperative period from 81.8 +/- 24.0 to 15.4 +/- 8.9 mm Hg was demonstrated (p < 0.001). Overall 25-year survival was 57%. Fourteen surviving patients (56%) have undergone subsequent procedures (n = 18) from 5 months to 16 years postoperatively (mean, 6.9 years) because they developed a recurrent left ventricular-to-aortic gradient of 58 +/- 28 mm Hg (p < 0.002). One patient underwent heart transplantation. All other late survivors have normal left ventricular function as determined by serial echocardiography.
Conclusions:
Apical aortic conduit is effective in relieving complex left ventricular outflow tract obstruction and improving left ventricular performance with acceptable short-term and midterm results, but late complications caused primarily by conduit tissue valve dysfunction are frequent in children. Since the early 1990s, the apical aortic conduit procedure has been largely replaced with the Ross or Ross-Konno procedure in our pediatric practice.
